Even following best practices, determining what object is on which layer can be difficult. Luckily, there is a quick way you can find out which layer contains an image without a lengthy investigation of the Layers palette.
To do so, press Ctrl and right-click the image in Windows, or press Control-Option and click the image on the Mac. In the resulting pop-up menu, the layer that contains the image appears at the top. To activate the layer, choose it from the pop-up menu.
